JPH0781676B2 - Electric pump of single main pipe type centralized lubricator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention connects a plurality of distribution valves to one main pipe, and mainly uses the lubricant measured by each distribution valve in a crane vehicle, a power shovel, or the like. The present invention relates to an electric pump of a single main pipe type centralized lubrication device that is supplied to a lubrication point of a construction machine.

(Prior Art) Conventionally, an electric pump of this type of single main pipe type centralized lubricating device is
For example, as described in Japanese Utility Model Publication No. 52-150 and as shown in FIG. 8, a pump element (A) communicating with a tank (T) loaded with a lubricant, a pilot switching valve (B), This switching valve (B) is equipped with two first
And a spool (C) having second lands (a) and (b) are movably arranged, a spring (D) is provided on one side in the axial direction of the spool (C), and a pilot is provided on the other side. A discharge passage (H), which forms a chamber (E), is communicated with the discharge side of the pump element (A), and is connected to a plurality of distribution valves (G) via one main pipe (F). And also
A pilot passage (I) that connects the pilot chamber (E) to the discharge passage (H) side and a pressure release passage (J) that opens the pilot chamber (E) to the tank (T) side are provided. Are configured.

The distribution valve (G) is provided with two first and second chambers (L) (M) defined by a piston (K).
A chamber (L) communicates with the main pipe (F), and a measuring cylinder (N) selectively communicates with the chambers (L) (M) as the piston (K) moves. Then, the piston (K) is applied by pressurizing the main pipe (F) side.
Is moved to discharge the lubricating oil in the second chamber (M) to a lubrication point, and the lubricant supplied from the main pipe (F) to the first chamber (L) is introduced into the cylinder (N). And then depressurize the main pipe (F) side to move the piston (K) back by the action of the spring (S), so that the lubricant measured in the cylinder (N) is transferred to the second Room (M)
To prepare for the next pressurizing step.

Thus, in the above configuration, the pump element (A)
8 is stopped, the spool (C) is held at the position shown in FIG. 8 by the pressing action of the spring (D), and the discharge passage (H) is held at the first land (a) of the spool (C). Is closed, and the communication between the pilot chamber (E) and the depressurizing passage (J) is blocked at the second land (b),
The main pipe (F) is opened to the tank (T). In addition, when the pump element (A) is driven from the above stopped state, the lubricant discharged from the pump element (A) has the discharge passage (H) in the first land (a). Since it is closed, it is supplied from the discharge passage (H) through the pilot passage (I) to the pilot chamber (E), and by this supply, the pressure in the pilot chamber (E) rises and the spool (C) ) Moves against the spring (D), the second land (b) closes the pressure relief passage (J) and the discharge passage (H) is opened, and a lubricant is added to the main pipe. It is supplied to each distribution valve (G) side via (F). Furthermore, after the lubricant is supplied to each of the distribution valves (G) and the lubrication at the lubrication points is completed, the pump element (A) is stopped, and this stop causes the spool (C) to move the spring (D). ), The main pipe (F) is opened to the pressure release passageway (J) and depressurized, and the piston (K) of each distribution valve (G) is returned by the action of the spring (S), The measured lubricant is supplied to the second chamber (M) to prepare for the next oil supply.

(Problems to be solved by the invention) However, in a single main pipe type centralized lubrication device, in order to supply a lubricant to each distribution valve (G) side to perform measurement, the main pipe (G) side It is necessary to repeat pressurization and depressurization of the pump element, but like the above electric pump, the pump element (A)
When using a pilot switching valve (B) that is operated by switching between starting and stopping, problems do not occur easily when using lubricating oil or low-viscosity grease as the lubricant, but use a high-viscosity lubricant as the lubricant. Even when the pump element (A) is stopped when it is used or when it is used in a low temperature condition, the pressure drop of the pilot chamber (E) in the pilot switching valve (B) causes a decrease in the pump element ( Since the leakage occurs from A), there is a problem in that there is a delay in time, rapid depressurization cannot be performed, and the lubrication cycle from the distribution valve (G) is hindered.

The present invention has been made in view of the above problems, and an object thereof is to apply pressure and depressurize on the main pipe side even when using a high-viscosity lubricant or when using under low temperature conditions. It is an object of the present invention to provide an electric pump of a single main pipe type centralized lubrication device capable of reliably performing oil supply from a distribution valve.

(Means for Solving the Problem) The present invention relates to a pump element (3) that operates in conjunction with a motor (2), a tank (4) that communicates with the suction side of the pump element (3), and the pump. In an electric pump of a single main pipe type centralized lubrication device, which comprises a discharge passage (6) communicating with the discharge side of an element (3), the discharge passage (6) is provided in the tank (4) in a pump body (1). A depressurizing passage (7) that opens to the motor is provided, and the motor (2) can be rotated forward and backward.
Depressurization valve (8) that operates in conjunction with the reverse rotation of the motor (2)
Is provided, and the depressurizing valve (8) is installed in the depressurizing passage (7). The pressure release valve (8)
Is interposed between the valve body (81), the interlocking body (82) that reciprocates in association with the forward and reverse rotation drive of the motor (2), and the valve body (81) and the interlocking body (82). And an elastic body (83) for biasing the valve body (81) in the closing direction and opening the valve body (81) when the pressure in the discharge passage (6) is abnormally high. It is preferable.

Further, the depressurization valve (8) is composed of a switching valve having a switching spool (91), and a reciprocating body (9) that reciprocates in conjunction with the forward and reverse rotation drive of the motor (2) on the spool (91).
It is also possible to connect 2).

Further, the pump body (1) has a discharge pressure detection passage (9) communicating with the discharge passage (6) and the detection passage (9).
And an indicator (10) which is installed in the interior and which operates in response to an increase in discharge pressure, and which also includes this indicator (10)
A sensor (11) for detecting the operation of (1) and giving a reverse rotation command to the motor (2) may be provided.

The motor (2) is composed of a DC motor capable of forward and reverse rotation, and is driven in reverse by turning on a depressurization detection sensor (11) for detecting depressurization pressure, and stopped by turning off the sensor (11). It is preferable to include a motor control circuit (12).

(Operation) The lubricant in the tank (4) moves from the discharge passage (6) of the pump body (1) to the distribution valve side by the operation of the pump element (3) accompanying the normal rotation driving of the motor (2). Is supplied to. Then, a predetermined amount of lubricant is supplied to the distribution valve side, and after the oil supply in each distribution valve is completed, the motor (2) is driven in reverse to drive the depressurization valve (8).
Is activated, the depressurizing passage (7) that houses the depressurizing valve (8) is forcibly opened to the tank (4) side, and the depressurizing of the discharge passage (6), that is, the main pipe is immediately performed. To be seen. As described above, by forcibly depressurizing the distribution valve side by the operation of the depressurization valve (8) by the reverse drive of the motor (2), for example, when using a high-viscosity lubricant or at a low temperature. Even when it is used under the conditions, it is possible to precisely supply oil from the respective distribution valves.

Further, the depressurization valve (8) and the valve body (81) and the interlocking body (8) that reciprocates in association with the forward and reverse driving of the motor (2).
2) is interposed between the valve body (81) and the interlocking body (82) to urge the valve body (81) in the closing direction, and the pressure in the discharge passage (6) is abnormally high. At this time, when the valve body (81) is composed of an elastic body (83) for opening operation, the valve body (81) is retracted by the reverse rotation of the motor (2), and the depressurizing passage (7) is moved. By opening the valve, the depressurization is performed immediately, and when the discharge passage (6) becomes abnormally high in the case where a failure occurs in the distribution valve or the like, the valve body (81) Since the discharge passage (6) is opened by the opening operation, the depressurization valve (8) also serves as a safety valve, and the structure has excellent safety.

The depressurizing valve (8) is composed of a switching valve having a switching spool (91), and the switching spool (91) reciprocates in association with the forward and reverse driving of the motor (2). Since the discharge passage (5) is switched to the depressurizing passage (7) by the operation of the switching spool (91) accompanying the forward and reverse rotation of the motor (2) when the 92) is connected, depressurization can be performed.
Depressurization is performed more reliably.

Further, a discharge pressure detection passage (9) communicating the pump body (1) with the discharge passage (6), and the detection passage (9).
And an indicator (10) which is installed in the interior and which operates in response to an increase in discharge pressure, and which also includes this indicator (10)
When a sensor (11) for detecting the operation of the motor (2) and giving a reverse rotation command to the motor (2) is provided, an increase in the discharge pressure at the completion of refueling is detected on the distribution valve side to issue a reverse rotation command for the motor (2). The reverse rotation command can be accurately given to the motor (2) with a wiring configuration shorter than the case where it is given.

Further, by using a direct-current / reverse-current DC motor as the motor (2), the depressurization detection sensor (11) for detecting depressurization pressure is turned on to reversely drive the sensor (1).
By providing the motor control circuit (12) which is stopped by the off operation of 1), the forward / reverse control of the motor (2) can be easily performed.

(Embodiment) The one-main-pipe centralized lubricating device shown in FIG. 1 is an electric pump (P) and a plurality of distributions connected to the electric pump (P) through one main pipe (S). It is composed of a valve (V).

The electric pump (P) has a pump element (3) which is operated in conjunction with a motor (2) in the pump body (1), and sucks the pump element (3) in the pump body (1). A suction passage (5) communicating with a tank (4) loaded with a lubricant is formed on the side, and the main pipe (S) is provided on the discharge side of the pump element (3) in the pump body (1). Is provided with a discharge passage (6). Further, the pump element (3) reciprocates in the cylinder chamber (31) communicating with the suction passage (5) and in the cylinder chamber (31), as is clear from FIGS. 5 and 6. And a piston (32) provided so that the piston (3
2) is connected to the front end side of a crank (34) inserted into an eccentric cam (33) fixed to the rotary shaft (21) of the motor (2), and is rotated as the motor (2) rotates. By reciprocating the piston (32) in the cylinder chamber (31) via a crank (34), the tank (4)
The lubricant supplied from the inside of the cylinder chamber (31) through the suction passage (5) to the discharge passage (6),
The discharge valve (61) interposed in the discharge passage (6) is opened, and the lubricant is supplied from the discharge passage (6) to the main pipe (S) side by opening the discharge valve (61). I am trying.

The distribution valve (V) has a plurality of metering cylinders (51) communicating with the main pipe (S) in the valve body (50), and metering pistons (52) in the cylinders (51). In addition to being provided so as to be reciprocally movable, a pilot valve (53) is provided on the side of the cylinder (51) connected to the main pipe (S), and a spring (54) is provided between the pilot valve (53) and the piston (52). ), While inside the valve body (50),
A lubricant introducing passage (55) extending from the connection side to the main pipe (S) near the pilot valve (53) to the rear side of the piston (52) in the cylinder (51) is formed, and the cylinder is also provided. A discharge passage (56) extending from the intermediate portion of the piston (52) in the reciprocating direction in the (51) to the outside of the valve body (50) is formed.

The pilot valve (53) communicates the introduction passage (55) with a metering chamber (57) provided between the metering piston (52) and the pilot valve (53) during depressurization, which will be described later. It has a passage (53a).

In the above configuration, when the motor (2) is rotated in the forward direction, the pump element (3) is driven by this rotation to supply the lubricant from the discharge passage (6) to the main pipe (S) side.
By supplying oil to the main pipe (S), the pilot valve (53)
Operates, and the lubricant of the main pipe (S) flows into the introduction path (55).
Is introduced to the rear side in the reciprocating direction of the piston (52) in the cylinder (51), the piston (52) moves forward with this introduction, and a predetermined amount of lubrication measured in the measuring chamber (57) The agent is supplied from the discharge passage (56) mainly to lubricating points of construction machines such as crane trucks and power shovels. After completion of refueling in each distribution valve (V), the pilot valve (53) is returned by depressurizing as will be described later, and the piston (52) is pushed by the pressing action of the spring (54). The lubricant that has returned and is introduced to the rear side of the piston (52) is transferred to the cylinder (51) through the introduction path (55) and the communication path (53a) provided in the pilot valve (53). ) In the measuring chamber (57) to prepare for the next refueling. Incidentally, in Fig. 1, (CB)
Is a control box that houses a control circuit (12) for the motor (2), which will be described later.

Therefore, in the electric pump (P) of the single main tube type central lubrication device as described above, the discharge passage (6) is provided inside the pump body (1) via the suction passage (5) to the tank ( 4) Forming a depressurizing passage (7) that opens to the side,
A depressurizing valve (8) is provided in the depressurizing passage (7), and a motor capable of forward and reverse rotation is used as the motor (2). The depressurizing valve (8) is interlocked with the reverse drive of the motor (2). 8) is opened and the depressurization valve (8) is opened to depressurize the main pipe (S) communicating with the distribution valve (V).

The pressure relief valve (8) shown in FIGS. 1 to 4 includes a valve body (81) arranged on the opening side of the pressure relief passage (7) to the discharge passage (6) and the motor (2). ) The interlocking body (82) reciprocating in conjunction with the forward / reverse drive of (1) and the valve body (81).
And an elastic body (83) interposed between the elastic body (83) and the interlocking body (82), and the elastic body (83) normally urges the elastic body (83) in the closing direction by the backward movement of the interlocking body (82). When the pressure can be released by opening the valve body (81) and the distribution valve (V) or the like has failed, when the pressure in the discharge passage (6) becomes abnormally high, With this high pressure, the valve body (81) is opened against the elastic body (83), and the high pressure on the discharge passage (6) side can be released to the tank (4) side. It has a shape. Further, when interlocking the interlocking body (82) and the motor (2), the interlocking body (82) is integrally rotatably attached to the rotary shaft (21) of the motor (2), and the operating pin (84) is projected to the outer peripheral edge. An eccentric cam plate (85) provided, and a sliding body (87) movably supported by the interlocking body (82) over a certain range and having a projection (86) projecting on the side opposite to the pin (84). Using the above, the operating pin (84) of the eccentric cam plate (85) is brought into contact with the projection (86) of the sliding body (87) in accordance with the forward and reverse driving of the motor (2), and the sliding body (87) is ) Is moved back and forth, and this sliding body (8
5) With the interlocking body (82), the valve body (81) has a first position where the valve body (81) closes the opening side of the discharge passage (6) in the depressurizing passage (7) and the valve body (81). It is located on the inner side of the depressurization passageway (7) away from the opening side and is reciprocated to a second position for depressurizing the distribution valve (V) side. Further, two engaging grooves (88) (89) are provided on the outer peripheral surface of the interlocking body (82) at predetermined intervals, and the engaging grooves (88) (89) and the engaging grooves are provided. (88) (89) An engaging body (90) mainly made of a ball that elastically engages with one of
A detent mechanism composed of and is provided, and the interlocking body (82)
Can be held at the first and second positions. still,
First and second springs (100) (101) for holding the sliding body (87) in a sliding direction neutral position are provided between both end surfaces of the sliding body (87) and the interlocking body (82). When the motor (2) is normally driven, the sliding body (87) is moved against the first spring (100), and the interlocking body (82) is held at the first position by the detent mechanism. Therefore, after the interlocking body (82) is held at the first position, the sliding body (87) reciprocates by the rotation of the eccentric cam plate (85), but the sliding force of the first spring (100) is increased. Sliding body by force (8
7) is designed to return to the neutral position. Next, when the motor (2) is reversely driven, the operation pin (84)
Comes into contact with the projection (86) of the sliding body (87), the sliding body (87) moves against the second spring (101), and the interlocking body (82) is moved to the second position by the detent mechanism. After being held, the sliding body (87) can be returned to the neutral position as in the normal rotation.

In the embodiment shown in FIGS. 1 to 4, the pump body (1) is provided with a discharge pressure detection passage (9) communicating with the discharge passage (6), and the detection passage (9) is provided. ) Is equipped with an indicator (10) that moves when the discharge pressure in the discharge passage (6) rises, and a sensor (11) consisting of a limit switch is arranged on the movement track of this indicator (10). Thus, when the discharge pressure in the discharge passage (6) rises, a reverse rotation command is given from the sensor (11) to the motor (2) side.

Then, from the electric pump (P) to the distribution valve (V)
When the lubricant is supplied to the side, as shown in FIG. 2, it is performed by driving the motor (2) in the normal direction, and by this normal rotation, the depressurizing valve (8) is interlocked. The body (82) is interlocked, and the valve body (81) is located at the first position for closing the depressurization passage (7). In such a state,
Due to the operation of the pump element (3) associated with the normal drive of the motor (2), the lubricant in the tank (4) is
It is supplied from the discharge passage (6) of the pump body (1) to the distribution valve (V) side through the main pipe (S). Then, a predetermined amount of lubricant is supplied to the distribution valve (V) side, and the oil supply at the distribution valve (V) is completed, and the main pipe (S)
When the pressure at rises, as shown in FIG.
The pressure in the detection passage (9) also rises, the indicator (10) arranged in the detection passage (9) is moved, and the sensor (11) provided on the movement locus is actuated. A reverse rotation command is output to the motor (2) side. In addition, the motor (2) is instructed by the sensor (11).
When the pressure is reversed, the interlocking body (82) of the depressurization valve (8) moves to the left and the valve body (81) disengages as shown in FIG. 4 through the process shown in FIG. Since the pressure passage (7) is located at the second position where the pressure passage (7) is opened, the depressurization passage (7) is opened to the discharge passage (6), and the main pipe (S) is depressurized with this opening. Of. As described above, by forcibly depressurizing the main pipe (S) by operating the depressurizing valve (8) by the reverse driving of the motor (2),
Even when a high-viscosity lubricant is used or when it is used under low temperature conditions, depressurization can be performed quickly, and this depressurization allows accurate operation of the distribution valve (V). Further, as shown in FIGS. 5 and 6, the depressurization valve (8) selectively supplies the lubricant to the distribution valve (V) side and depressurizes the distribution valve (V) side. It is also possible to use a switching valve for switching to. That is, as shown in FIG. 6, a switching spool having two first and second lands (91a) and (91b) and a small diameter portion (91c) provided between these lands (91a) and (91b). Using (91), the switching spool (91) and the interlocking body (92) that reciprocates in conjunction with the rotating shaft (21) of the motor (2) are connected via a connecting pin (93). Let
The interlocking body (92) is reciprocally driven by the forward and reverse rotation drive of the motor (2) to switch the spool (91). Specifically, an eccentric cam (33) fixed to the rotary shaft (21) is formed in a part of the peripheral surface of the interlocking body (92) with an engaging groove (94) extending in the length direction thereof.
Is inserted into the engaging groove (94) of the interlocking body (92) at a side portion of the crank (34) to which the piston (32) of the pump element (3) is connected. The projection (95) to be engaged is integrally formed. In addition, springs (9
6) and two floating prevention pins (97) (97) are provided, and the interlocking body (92) is supported by these pins (97) and springs (96).

Then, when the rotation shaft (21) is driven in the reverse direction, the interlocking body (92) is engaged by the engagement of the protrusion (95) and the engagement groove (94).
By moving each land (91) of the switching spool (91).
The small diameter portion (91c) located between a) and 91b is connected to the communication passage (6a) extending from the discharge passage (6) and the suction passage (5) as shown in FIG. Each of these communication passages (6a) can be located by connecting to the passage (5a).
By communicating with (5a), the main pipe (S) is depressurized. Further, when the rotating shaft (21) is driven in the normal direction, the interlocking body (92) is moved in the opposite direction (to the right) with respect to the position shown in FIG. 6, and the first land (91a) of the spool (91) is moved. )
And the communication passage (6a) of the discharge passage (6) and the suction passage (5)
The connection part with the communication passage (5a) is closed, and the lubricant is supplied from the discharge passage (6) to the distribution valve (V) side through the main pipe (S). Incidentally, in FIG. 6, an O-ring (98) is provided around the outer periphery of the second land (91b) of the switching spool (91), and the moving position of the spool (91) can be held by this ring (98). I am trying.

Further, it is preferable that the motor (2) is a direct-current motor capable of forward and reverse rotation. In this case, the forward / reverse drive control of the motor (2) is performed by the motor control circuit (12) shown in FIG. 7 using a depressurization detection sensor.

That is, the control circuit (12) shown in FIG. 7 is used to turn on the operation switch of a main machine to be lubricated, such as a machine tool, which lubricates a power line connected to a DC power source such as a battery. A system that intervenes a key switch (KS) that is turned on in conjunction with an instantaneous contact (62G) of a signal timer (62G), which will be described later, and that integrates the operating time of the main engine and outputs a refueling command at predetermined time intervals. While connecting a timer (2G), an integration auxiliary relay (16) that excites when the key switch (KS) is turned on between the power supply lines and outputs an integration instruction to the system timer (2G).
GX) and the indicator (10), and the contact (33G) of the limit switch (11) that constitutes the depressurization detection sensor) and the contact (33G) are turned on, for example, 5
The on-delay relay (DL) that excites with a delay of ~ 10 seconds is connected in parallel with the series circuit, and the next control circuit is connected in parallel.

Normally open contact (DL) of the on-delay relay (DL),
The on-delay relay is connected in parallel with the system timer (2G) instantaneous contact (2G), pushbutton switch (3-88G), and motor operation auxiliary relay (33GX1) normally open contact (33GX1) described later. The normally closed contact (DL) of (DL) and the parallel circuit of the driving auxiliary relays (33GX1) (33GX1) are connected in series, and the motor (2) and the driving auxiliary relay are connected. (33GX1) (33GX2) Motor control circuit that connects a series circuit with a parallel circuit (33GX1) (33GX2) of normally open and normally closed contacts Is turned on, the operation auxiliary relays (33GX1) (33GX2) are excited and the motor (2)
Is excited when the is operated, starts counting at the same time as refueling starts, and when the contact (33G) of the limit switch (11) does not turn on even if the preset refueling required time (for example, 10 minutes) is exceeded, refueling is performed. A signal timer (62G) for judging an abnormality and notifying the abnormality, a time contact (62G) for self-holding the timer (62G), and the operation auxiliary relay (33G)
An abnormality detection control circuit in which a parallel circuit of (X1) is connected in series.However, when the key switch (KS) is turned on, the auxiliary relay (16GX) is excited and the system timer (2G) causes the key switch (2G) to operate. KS) ON operation time is integrated and a refueling command is output every predetermined time.
That is, when the operation time of the main engine has passed a predetermined time, the contact (2G) is generated by turning on the system timer (2G).
Is entered, each of the operation auxiliary relays (33GX1) (33GX2) is excited to switch each contact (33GX1) (33GX2) of the auxiliary relay in the motor control circuit, and the motor (2) is connected to the solid line in FIG. Current flows as shown by the arrow,
The normal rotation drive of the motor (2) is performed, and the lubricant is supplied to the distribution valve (V) side. When the instantaneous contact (2G) of the system timer (2G) is turned on,
When the auxiliary relay (33GX1) is excited, its normally open contact (33GX1)
When 1) turns on, self-holding works and the drive of the motor (2) is continued. And the distribution valve (V)
When the refueling is completed and the pressure in the discharge passage (6) rises, the contact (33G) of the limit switch (11) is turned on, and the delay relay (DL)
Is excited for a certain period of time (5 to 10 seconds) and then its normally closed contact (D
L) opens, the excitation of each of the auxiliary relays (33GX1) (33GX2) is released, each contact (33GX1) (33GX2) is switched, and the delay relay (DL) is connected to the motor (2).
A current flows through the normally open contact (DL) of the motor as shown by the dotted arrow in FIG. 7, and the motor (2) is driven in the reverse direction, and this reverse rotation communicates with the distribution valve (V). The main pipe (S) is depressurized. Further, when the pressure is released and the contact (33G) of the limit switch (11) is turned off, the excitation of the delay relay (DL) is released and the energization of the motor (2) is stopped. To be done. Also, the signal timer (62G) is operated in accordance with the excitation of the auxiliary relay (33GX1), and the signal timer (6G) is activated.
Even when the fixed time is counted by 2G) and the count is finished, the motor (2) is stopped by the OFF operation of the contact (62G).

(Effects of the Invention) As described above, the electric pump of the single main-tube centralized lubricating device according to the present invention has the depressurization that opens the discharge passage (6) to the tank (4) side in the pump body (1). In addition to providing the passage (7), the motor (2) for driving the pump element (3) can be rotated forward and backward, and a depressurizing valve (8) that operates in conjunction with the reverse rotation of the motor (2) is provided. (8)
Since the depressurizing passage (7) is installed in the depressurizing passage (7), depressurization of the discharge passage (6) communicating with the distribution valve by the operation of the depressurizing valve (8) by the reverse driving of the motor (2), that is, the main pipe (S)
It is possible to forcibly depressurize. Therefore,
Even when a high-viscosity lubricant is used or when it is used under low temperature conditions, depressurization is quick, accurate operation can be performed on the distribution valve side, and accurate lubrication is possible.

The depressurization valve (8) includes a valve body (81) and the motor (2).
With the interlocking body (82) that reciprocates in conjunction with the forward and reverse drive of
Interposed between the valve body (81) and the interlocking body (82),
The valve body (81) is biased in the closing direction, and the discharge passage (6)
When the pressure is abnormally high, the valve body (81) is constituted by an elastic body (83) for opening operation, so that the depressurization can be performed quickly and a failure may occur in the distribution valve or the like. In this case, the depressurization valve (8) can also be used as a safety valve, and the safety can be improved.

The depressurizing valve (8) is composed of a switching valve having a switching spool (91), and the switching spool (91) reciprocates in association with the forward and reverse driving of the motor (2). By connecting 92), the discharge passage (5) can be switched to the depressurizing passage (7) by the operation of the switching spool (91) accompanying the forward and reverse rotation of the motor (2), so that depressurization can be performed.
The depressurization can be performed more reliably.

Further, a discharge pressure detection passage (9) communicating the pump body (1) with the discharge passage (6), and the detection passage (9).
An indicator (10) which is installed in the vehicle and operates in response to a rise in the discharge pressure, and a sensor (1 which detects the operation of the indicator (10) and gives a reverse rotation command to the motor (2).
1) is provided, the motor (2) can be configured with a simpler wiring structure than in the case where a rise in the discharge pressure at the completion of refueling is detected on the distribution valve side and a reverse rotation command for the motor (2) is given. ) Can be accurately given a reverse rotation command.

Further, a forward / reverse DC motor is used as the motor (2), the reverse operation is driven by turning on the depressurization detection sensor (11) for detecting the depressurized pressure, and the driving is stopped by turning off the sensor (11). By providing the motor control circuit (12), the forward / reverse control of the motor (2) can be easily performed, and the oil supply from the distribution valve can be reliably performed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the overall structure of a single main pipe type centralized lubricating apparatus equipped with an electric pump of the present invention, and FIG. 2 is an explanatory view for explaining an operation mechanism of a depressurizing valve in the electric pump, FIGS. FIG. 4 is an explanatory view for explaining its operation state, FIG. 5 is a side sectional view showing another embodiment, FIG. 6 is a sectional view of the same plane, FIG. 7 is a motor control circuit diagram, and FIG. It is sectional drawing which shows a prior art example. (1) …… Pump body (2) …… Motor (3) …… Pump element (4) …… Tank (6) …… Discharge passage (7) …… Depressurization passage (8) …… Depressurization valve (81 ) …… Valve body (82) …… Interlocking body (83) …… Elastic body (91) …… Spool (92) …… Interlocking body (9) …… Detection passageway (10) …… Indicator (11) …… Sensor (12) …… Motor control circuit

Claims (5)

[Claims] 1. A pump element (3) operating in conjunction with a motor (2), a tank (4) communicating with the suction side of the pump element (3), and a discharge side of the pump element (3). In an electric pump of a single main tube type centralized lubrication system provided with a discharge passage (6) communicating with each other, a depressurizing passage (7) for opening the discharge passage (6) to the tank (4) is provided in a pump body (1). )
And a depressurization valve (8) that operates in conjunction with the reverse rotation of the motor (2) to enable forward and reverse rotation of the motor (2). The depressurization valve (8) is provided in the depressurization passageway (7).
An electric pump for a single main pipe type centralized lubrication device, which is characterized by being installed inside. 2. A reciprocating body (8) for reciprocating a depressurizing valve (8) in conjunction with forward and reverse driving of a valve body (81) and a motor (2).
2) is interposed between the valve body (81) and the interlocking body (82) to urge the valve body (81) in the closing direction, and the discharge passage (6)
2. The electric pump for a one-main-pipe centralized lubricating device according to claim 1, wherein the electric pump comprises an elastic body (83) for opening the valve body (81) when the pressure of the main body is abnormally high. 3. A depressurizing valve (8) comprises a switching valve having a switching spool (91), and a reciprocating body (9) which reciprocates in the spool (91) in association with forward and reverse driving of a motor (2).
2. The electric pump for a single main pipe type centralized lubricating device according to claim 1, wherein 2) is connected. 4. A pump main body (1) is provided with a discharge pressure detection passage (9) communicating with the discharge passage (6), and an indicator installed in the detection passage (9) and operated in response to a rise in discharge pressure. (1) The one-main-pipe centralized lubricating device according to claim 1, further comprising a sensor (11), which is provided with (10) and which detects an operation of the indicator (10) and gives a reverse rotation command to the motor (2). Electric pump. 5. The motor (2) is composed of a direct-current / reverse-current DC motor, and is driven in reverse by turning on a depressurization detection sensor (11) for detecting depressurization pressure, and by turning off the sensor (11). The electric pump for a single-pipe centralized lubricating system according to claim 1, further comprising a motor control circuit (12) for stopping.